


Exposed

by tinygaydream



Series: Hina's Disguise [2]
Category: BanG Dream! (Anime), BanG Dream! Girl's Band Party! (Video Game)
Genre: F/F, Hina POV, Incest, POV Second Person, Romance, Sibling Incest, Twincest, soft
Language: English
Status: Completed
Published: 2020-08-10
Updated: 2020-08-10
Packaged: 2021-03-05 22:35:35
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 5,083
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25812907
Author URL: https://archiveofourown.org/users/tinygaydream/pseuds/tinygaydream
Summary: In the aftermath of the Roselia concert, all you can do is make your way back home with a million thoughts and feelings swirling around inside you. Back home… to Sayo.[Sequel to Mistaken Identity]
Relationships: Hikawa Hina/Hikawa Sayo
Series: Hina's Disguise [2]
Series URL: https://archiveofourown.org/series/1872826
Comments: 10
Kudos: 70





	Exposed

**Author's Note:**

> Y’all asked for this, and I’m more than happy to provide! It’s really soft and vanilla, but I’m still happy with how it came out. As always, I love to hear your thoughts, so leave a comment if you have the time!

It doesn’t take long for the adrenaline rush to pass, and right after leaving the studio where you dropped off your disguise is when it hits you all at once.

Those were _Sayo’s_ lips on yours.

Your phone buzzes in your pocket. You ignore it.

Your _sister_.

And then you kissed her back, and you liked it. A lot.

Your phone buzzes again, but you’re still too lost in thought to care. Thankfully, you have your wits about you enough not to get run over in the streets. Barely.

And now you’re going to go home and...

Is this a terrible idea? If there’s ever a time for you to second-guess your life’s choices, now would be the time, right?

It doesn’t help that you’re still kind of _really worked up_. Stupid Sayo and her stupid feelings making you realize important things about your sexuality. You didn’t ask for this. Probably.

One more buzz from your pocket, and you finally check your phone, a little irritated that you’re even more popular than usual today, apparently.

 ** > Aya: **you ok?  
** > Aya: **hina????  
** > Aya: **everyones super worried! you barely even noticed us in the studio  
** > Aya: **(chisato pretends not to be but i know she is too)  
** > Aya: **guessing the concert thing didnt go super well? :/  
** > Eve: **hope you feel better soon!  
** > Maya: **take care of urself, ok?!

You’re... gonna have deal with that eventually. Like, what are you even supposed to say? “It’s cool, Sayo just came on to me while I was disguised and now it turns out I really want her to bang me, and also I wonder if I’ve felt this way all along?”

There’s probably a better way to phrase that, but for now you can’t think of one, so in what’s gotta be the first smart decision you’re making today, you decide to leave that for when you feel a little more in control.

 ** > Hina: **im fine! in a rush, sorry, will explain tomorrow!

It’s not great, but it’ll have to do. Hopefully you can come up with a reasonable enough explanation by the time you have to deal with this again. Worst case, well, you’re smart enough to figure out how to change your name and move to a different country without getting caught. You could start a new life as Awakih Anih, talented musician with a mysterious past and kind of an unusual name.

Moving on to more important matters! You’ve somehow zombie-walked dangerously close to your home, and you still haven’t a clue how you’re supposed to approach her. _If_ you should approach her. You could always give yourself a couple of days to figure out a plan, but then there’s the risk that your sister manages to properly seal up and rationalize all her stupid feelings again, and that’s not gonna help.

Ah well. Diving in headfirst without a plan is more your style anyway. Like most things in life, maybe you’ll get lucky and manage to wing this one too.

You try to open the door to your home... only to find out that it’s already unlocked. Welp.

So, good news first, your sister made it home, is probably in her room and relatively unharmed, and your parents are almost definitely still at that staff meeting they were supposed to go to this evening.

Now for the bad news. Forgetting to lock the door behind her is sufficiently uncharacteristic of Sayo that there’s no way she’s anything other than an absolute wreck right now. Getting through to her—getting her to even _talk_ to you—may end up being a bit of a challenge.

It’s eerily quiet as you enter the hallway. You suppose it’s not technically any different from any other time you’re the first one home, but the silence feels... thicker.

Or maybe that’s just your nerves talking.

Alright. First things first. You drop off your guitar and school bag in your room, making sure not to make too much noise. Maybe you’re being paranoid, but you don’t want your sister to hear you and give her ample time to put up her defenses. Not today.

Because you’re feeling like being a good sister today, you even make sure to pick up Sayo’s bags dropped all over the hallway and put them next to her bedroom door. At the very least she’ll be able to avoid a lecture from dad about respecting one's personal belongings without having to come up with a convincing lie. That’s probably in your best interests too.

After spending another few minutes just pacing around because _are you honestly going to do this,_ you end up in front of Sayo’s door. It doesn’t take you putting your ear against it to notice that she’s... very obviously crying, and it just breaks your heart.

For someone who’s so boppin’ and amazing and cool and... well, you could go on, she is just so flipping hard on herself. This isn’t the first time you’ve heard her cry in her room—normally those are the days you opt to give her some space instead of barging in, because what are you supposed to do without just making things worse, really?—and it’s always because of those stupidly high standards she sets for herself.

If there is one thing you wish you could just get through that thick skull of hers, it’s that she’s _already_ the most zapping person in the whole world and she really should be nicer to herself since she’s basically perfect just the way she is and _wow_ have you _always_ been this obviously smitten?

Alright. No more stalling. You can do this.

Maybe.

You take a deep breath, and...

...feel a little silly, because you’ve still not knocked on her door. When did you become such a coward?

Okay, on three. You just need to psych yourself up a little. One... two...

When you finally knock, it sounds uncomfortably loud in your ears, even though it’s not even close to the top ten overly bombastic entrances into Sayo’s room you’ve made over the years. Purely _objectively_ , compared to that time when you were ten and ran in showing off your skills with the kazoo, it’s positively proper.

You can no longer hear her crying, so that means she must’ve heard you, and it takes another few seconds before she answers.

“Hina? I’m not feeling too good right now, we can talk some other time.”

You’re actually impressed by how composed she sounds, if it weren’t completely infuriating for making your job all that much harder. If this music thing doesn’t work out for her, she can always take up acting. You also realize that you still haven’t actually thought about what you’re going to say to convince her to let you in, so... oops.

“I, um... heard you crying,” Wait, don’t draw attention to that! She _hates_ showing weakness, and it’ll probably just make her clam up more. “I mean. Urgh. Sorry. Look, can we talk? It’s important.”

Super vague, but even you have your weak moments, you suppose. Can’t expect pure brilliance all the time.

She scoffs. “It’s _really_ not a good time. You’ll have to wait until tomorrow.”

Uuuuuuuuugh. Why does she always get like this. Okay, let’s try that again.

“Please, sis? It won’t take long, and, um...”

Why does your brain decide that _now_ is the time to opt out of knowing all the right answers. You’d like to file a complaint with whoever’s responsible for this. Defective Hina brain, please send a replacement that knows how to talk to her sister without putting her foot in her mouth, thanks. Sayo doesn’t even answer this time, and you can’t really blame her.

You try to think of something better to say, but a minute later you start hearing music coming from her stereo, which is as clear a sign as any that you’ve been dismissed and she’s not gonna bother listening to anything else.

Oh, screw this. If you’re going to have to play the psychological game before you can come in, you’re going to be here all night, and your parents would probably disapprove of that.

Time to act the way you act best: unilaterally.

You take another deep breath.

“Okay, I know you don’t want to talk to me, but this is _really_ important and I don’t want to just talk to a piece of wood. You have one more chance to open up, or... or... I’ll _kick down the door_.” Maybe that’s a little too impulsive, even by your standards, but you mean it too.

Seconds pass.

It’s got to be almost half a minute, and you’re starting to worry that you’re going to have to follow through on that threat. You will, but...

Still nothing. _Oh crap, your parents are gonna be so mad._ Do you even know how or have the lower body strength to kick down a door? You’re good at most things you do, but even you can only stretch the limits of physics so far before it just stops being realistic. You also realize far too late that even _if_ you manage to, a hole where the door should be will make it hard to have what should be a very private sort of talk.

Well, you gave her a chance. You raise your thigh, bracing your leg and hoping it won’t hurt _too_ bad. Also that it’ll actually make a dent instead of just making you look dumb. Though if that gets her to come out and talk to you, that works, too.

And then Sayo finally opens the door. You can’t help the sigh of relief that escapes you. Disaster very narrowly avoided. Her expression’s unreadable, and her eyes are still red from crying. You suppose you already pointed that out earlier, so there’s no use pretending you didn’t see it.

She raises an eyebrow at your posture and crosses her arms. “Were you really going to kick in my door?”

“Yes!” you reply, far too loudly, because you’re still all kinds of worked up and full of adrenaline, so you clasp a hand in front of your mouth quickly.

“Yes,” you repeat, much softer this time. Not that she didn’t hear you the first time. “I’m tired of all this walking on eggshells. We’re going to flippin’ talk about how you’re feeling, eat all of this candy I stuffed in my pockets, cry a bunch, and you’re going to, uh, like it?”

A moment passes where you just stare at each other. You’re a little worried that she thinks you’ve totally lost it.

You grumble. “I had a point to make, I promise! It just got... sorta lost in all this. Look, can I come in? Please? It’ll be boppin’? You know you can’t say no to all this candy!” You pull a random assortment of gum and ‘fun size’ chocolate bars out of your pockets, and give her what you hope is a reassuring sort of smile.

It takes another few adrenaline-filled seconds before anything happens, and you worry you’re pushing this too much. Maybe you should’ve given her a night to sleep off the weirdness of it all instead of _literally threatening to kick down her door_ , then try more subtly in the morning, but then... Sayo actually smiles.

Granted, it’s a very watery smile. An “I don’t feel super zapping but I’m at least slightly amused” sort of smile.

So of course you can’t stop yourself from beaming at her as you let yourself into her room, ever the skillful opportunist that you are!

She turns around, still smiling slightly, “I didn’t say you could... oh what’s the point. Sure, you can come in.”

You make yourself comfortable on her bed and hug your knees to your chest, trying hard not to think of more... intimate activities you could do on there. After another second’s hesitation, she closes the door and actually sits next to you, her feet planted properly on the floor instead. Not leaning against you or even touching, of course. Definitely further away than you would’ve liked, but it’s still a good sign, probably!

“Sis... you don’t hate me anymore, right? I mean, I know we’ve got issues still,” she laughs humorlessly in response, “but we’re getting better. I think.” You take a couple seconds to get your thoughts together. “Like, we had fun at the Star Festival, and there was that whole astronomy club business…”

“Of course. Was this all you wanted to talk about? Surely it was something more urgent for you to threaten to destroy my door?”

She eyes you skeptically, and you can’t blame her. But hey, it’s not your fault that this is a really awkward subject to bring up! Even you, with your relative lack of shame, can’t quite bring yourself to outright _say_ it.

“Okay. Look. Let’s say that I heard from... someone... that you ran away after your concert today, and that, uh... it had something to do with me?”

She takes in a sharp breath, and you can see her put that neutral expression on her face. Your sister always does that when she gets uncomfortable and is about to put a whole bunch of walls up, and you _hate_ it. Damage control!

“I mean, it’s possibly that I’m just overthinking this, and there’s not actually anything serious, ahaha! I just... um...”

“Hina.”

You swallow at the focused expression she pins you with. It would’ve been kinda hot if you weren’t feeling distinctly uncomfortable and out of your element. “…Yes?”

“What _exactly_ did you hear?”

Okay, this is... you’re going to have to come clean about your whole zany scheme, aren’t you? Crap. There isn’t really a way to tell her that you _know_ without implying you had eyes in that same alley, and at that point what difference does it make?

“Okay, so... _please don’t be mad_ . I maaaaaybe had this crazy idea to go to the concert in disguise, just so I could see you! You were _so_ awesome, sis! I absolutely love seeing you all fired up on stage and... wait, that’s not important right now.”

She just raises her eyebrow at you, which is good because it means she’s not kicking you out yet, and you’re not detecting any anger yet.

“Um. Maybe it’s easier if I just... So, the disguise was, um...”

“Hina, I don’t like it when you come to my concerts without knowing about it, but is this really _so_ important that—“

“Shushushush. I’m getting there! Okay, so, let me know if this sounds familiar. The disguise I was wearing had, um, this white wig, which by the way was _weird_ , I don’t know how you deal with having such long hair, and I was wearing this nice black and red shirt, Aya did the makeup to make me look all different-y, and—”

Her eyes go wide as she realizes what you’re implying.

“—those jeans that actually looked _surprisingly_ bopping on me, it’s not something I would normally wear but maybe I will in the future with how well it works and oh flip you’re staring at me and you totally figured it out and I’m rambling please don’t hate me!”

Sayo moves a little closer to you, careful not to touch, and stares at you intently as if picturing in her head how the disguise would make it all fit together, “That was... you?”

You actually _blush_ and look away. Isn’t she supposed to be the one to get all flustered? “Maybe? ...Yes.”

“So in that alley when I kissed... you...”

You wave your hands dramatically. “I didn’t mean to let that happen! You were just really intense and it made me feel all fuzzy and zapping and good and. Um. Wait.”

She flushes bright red. “Y-You felt something too?” Narrowing her eyes at you, she continues, “I swear, Hina, this had better not be some elaborate prank.”

You make an indignant noise, because _okay_ maybe you like seeing your sister flustered a little too much, but even for you this would be pushing it several lightyears too far.

“It’s not a joke! It was actually really bopping! The boppingest, really. Even if I‘m pretty sure that means I’m pretty messed up in some way…”

“So you feel… the same way?” she asks, very quietly, and she looks so shy and it’s honestly the cutest thing you’ve ever seen.

“Well, yeah! I mean, probably? I hadn’t… really gotten to that point yet.” You look away, feeling shy as well. “I’d, uh, like to find out, though?”

She closes her eyes and groans. “I can’t believe I spent all this time here feeling bad about using someone else to forget you and then it turns out that... oh my _god_ Hina, you have _got_ to be the most infuriating sister anyone’s ever had to deal with.”

You’d like to protest that she’s at least as bad as you, you really would, but before you can come up with something incredibly witty to say she’s suddenly pushed you on your back and is looming over you with your wrists pinned against the mattress, her face far too close to yours, and words suddenly don’t... work...

Sayo blinks, but there’s a hint of a smile on her face. “If I’d known this would get you to shut up, I would’ve thrown you on my bed so much sooner.”

“I’m very okay with this approach,” you grin. You honestly feel so happy your eyes well up, because even if you’d really hoped for this talk to work out well, you weren’t actually expecting it to go like _this_. But now she’s _here_ like you’ve always wanted her to be, even if you were totally in denial about what that would look like, and you’ve got this feeling this time she won’t leave you hanging.

“I’ve still not forgiven you for sneaking into my concert, you know,” she whispers into your ear, and you’d like to pretend to be apologetic but instead it makes you shiver in an amazingly zappin’ sort of way.

An uncertain expression appears on her face, and she puts a little more distance between your face and hers.

“Is this... okay? I don’t want to move too fast for you.”

You snort, because _really._ If you didn’t want this to happen, would you really have come barging into her room the way you did? Still, it’s very considerate, and ridiculously cute how much she’s blushing. You’re kind of smitten, actually, and now that you’re thinking about this you _have_ to make sure she knows.

“It’s okay! You can, uh, move as fast as you like, honestly. Also...,” well, butts, you didn’t think you’d feel this awkward to tell her, “have I said lately how super beautiful and pretty you are?”

That sounded a lot smoother in your head.

She stares for a moment, and her face gets redder, but then she smirks. “We’re identical twins.”

“Still!” You pout, and now there’s definitely a genuine smile on her face. You’ve missed that so much! “I don’t get all the fluttery floopy feels when I look at _me_ in the mirror, so it’s totally different!”

Sayo keeps smirking, and it’s kinda hot but you honestly wish she would just _kiss_ you already. The tension’s getting a little ridiculous, and you can’t reach for her while she’s holding your wrists beside your head and straddling you like this.

Before you can complain, she leans in and brushes her lips against yours, pulling away immediately when you try to kiss her back.

A small whine escapes you. Because come on… really? She’s totally getting a kick out of this, isn’t she? The feeling of being in control for once, which means… is she turning _this_ into some kind of contest?

“Sayooo, come onnnnn…”

You almost think she’s taking pity on you, but instead she keeps teasing you over and over again. Nuzzling your lips, then pulling away before anything more happens, brushing against your cheek, the side of your neck, your ears, your throat…

“Siiiiiiiis… stop teasing me…”

She breathes in sharply and stares at you with hungry eyes. Huh. Something about what you said? Is it—

And then she kisses you.

There’s nothing gentle about it this time. Even compared to the kiss in that alley, this is just… wow. If you thought Sayo was aggressive then, it’s nothing compared to when she isn’t holding back. How long has she been holding this in while your touchy-feely attitude tormented her?

She pushes your wrists further into the mattress as she leans in closer, her upper body pressing up against yours as she deepens the kiss. You don’t know when you opened your mouth, but when you feel her tongue play with yours again you have to try your hardest to stop yourself from making another pathetic noise and interrupting the kiss.

“Hina…,” she moans, just like in the alley. This time, however, it doesn’t put a stop to what you’re doing. Instead, she releases one of your wrists and moves her hand slowly down your body, first cradling your cheek while she looks into your eyes, then moving further downwards.

You squirm a little at the ticklish feeling of her fingers against your side, until her hand reaches your butt and she _squeezes._ You gotta admit it feels pretty good, but then she pulls her hips against yours. Her thigh slips between yours and puts pressure on your groin, which feels _amazing_ and before you know it you’ve let another loud moan out.

“Sis…,” you whisper again, and her pupils widen. So she _does_ have a thing for that, huh?

“You have no idea how long I’ve wanted to do this to you,” she breathes into your ear, as she pushes you further into the bed with the thigh you’ve impulsively started grinding against.

Your thoughts are starting to feel foggy, but you still have enough clarity to feel a little bad about how long you must’ve accidentally worked her up. You’re also more than a little curious. “How… hnnng… how long?”

Sayo nips at your ear before answering. “Remember that play you were in our first year of high school? When I saw you dressed like that I had to stop myself from running up to you and just pulling you into an empty classroom with me…” she nips again, “…tearing off that princess costume…” she licks down your neck and you shiver and close your eyes, “…just taking you right there in the school during the intermission.”

And dang if that doesn’t get you even more worked up, even if you doubt it would’ve gone all that well if she tried at the time. You feel absolutely soaked and wish your sister would just _touch_ you because her words are making this even more overwhelming, and…

“Sayo… Sis… _please_ . I want you so much. _Please fuck me._ ”

Those last three words slip out and probably are what finally make her take pity on you. Her breath hitches, and without further fanfare she pushes her hand under your panties, no doubt feeling how drenched they’ve gotten, and slips two fingers between your lips.

It’s clumsy, and she’s probably never done this with someone else before, but then you’re new to this too and it honestly doesn’t matter because it’s _Sayo_ , and no matter what she does it just feels zapping anyway.

Her fingers run up and down your lips as she watches you carefully, seeing where you’re most sensitive, what spots make you moan the loudest, what drives you crazy. Even here you can tell she’s got that same sort of focused approach she always puts towards her guitar practice, but you doubt it matters much because _everything_ is a sweet spot when Sayo’s involved.

But maybe she’s learning more about what gets you worked up than you know yourself. You’d really like that, actually, if she were just plain better at touching you than you are yourself. Is that weird? You figure you probably shouldn’t say that.

However, all thoughts are banished from your mind when she pokes at your entrance with her index finger. She’s watching you intently, and you feel kind of warm at how careful she’s being to make sure she’s not making you incomfortable, but you also wish she would just get on with it already!

You make another pleading noise—totally on purpose, you swear!—and she pushes inside. Your moans are silenced as she immediately kisses you, her tongue brushing against yours even as she pumps her finger in and out of you.

It doesn’t take long before she adds a second finger, pumping in and out, and flicks her thumb against your clit in the process. You worry you’re running out of air in between all the moans and kisses, but thankfully she gives you a little space to breathe, even if it doesn’t stop her from biting at your ear and neck.

Slowly, you’re losing track of your surroundings. Even your so-called genius brain can’t handle all this stimulation. The noises you’re making—lewd ones, no doubt—where Sayo’s touching you— _everywhere_ —and how close you’re getting.

Finally, something inside you breaks, and one last flick against your clit pushes you over the edge.

You scream or… moan or… _something_ Sayo’s name interspersed with ‘sis’ and ‘love you so much’ over and over as your mind goes blank, and you’re vaguely aware that your sister is being uncharacteristically reassuring, whispering all sorts of nice things in your ear, and you almost wish you could tell what she was saying if you still had any brain cells left to be consciously aware of that fact.

“Shh… it’s okay, I’ve got you.”

Her fingers slow down while you come down from your orgasm, drawing it out but being careful not to overstimulate you further. She also wipes some tears from your eyes with her other hand, and you’re not entirely sure how that happened but it still makes you happy she’s being so gentle and loving that you immediately tear up again. Randomly, it occurs to you that maybe you can’t make fun of Aya as much anymore.

When you’ve calmed down slightly, Sayo wraps her arms around you, snuggling up close. All this time, she keeps whispering reassuring words in your ears, how she cares about you, wants to take care of you, and you swear there’s even a few “I love you”s in there. There’s more affection in that barrage of words than you think you’ve ever gotten from her in your entire life up to this point. You almost appreciate this even more than the sex itself.

Of course, the post-orgasm happiness and feeling like there’s nothing wrong in the world as long as you’re in your sisters arms can only last so long.

“Hina… what does this mean?”

It’s a good question. What _does_ this mean? She looks away and continues, “I don’t… I don’t want this to be just a temporary outlet for built up feelings, but…”

You think you understand where she’s going with this. “But we’re sisters?”

“Yeah…”

You smile mischievously, then reply, “That’s pretty hot.”

Sayo glares at you.

“I understand why it’s scary!” you’re quick to add, “I just… really want this to work, you know? I don’t know what that means yet either, but… I’d like to find out? With you?”

You wish you could give her something more definitive. Sayo’s always been the sort of person who doesn’t deal well with uncertainty, the sort of person who needs to know exactly what the next five to ten years of her life are going to look like, and that’s something you can’t give her here.

There is one thing you may be able to give her, though.

“Hey, sis? Will you be… my girlfriend?” She blushes a bright red immediately, and you quickly try to explain, “I know it can’t be, like, public knowledge or anything! But I’d love for it to feel a little more official, I guess?”

You’re blushing now, too. You suppose it’s important to you too. Even if you’re not all that much like Sayo, it would still feel really good to have _some_ reassurance that this isn’t just something the both of you do when you’re sexually frustrated but otherwise doesn’t mean anything.

“I’d love to.”

It’s quiet, and she’s looking off to the side as she says it, but you definitely heard! You grin widely at her, and after a few seconds, she returns a hesitant smile.

You unceremoniously flip her over. Now it’s _you_ pressing into your sister on her bed. She squeaks, which officially has to be the cutest sound you’ve ever heard someone make, and you stare into her eyes.

“Time to make my wonderful girlfriend feel good too, right?”

Just as you’re about to pay her back for all the moans she got out of your earlier, you hear the door slam and your mom’s voice—”I’m hoooome!”—coming up the stairs. You groan, because really? Timing, mom.

Sayo’s eyes have gone wide, and she immediately pushes you off and jumps off the bed, beginning to hide the mess you’ve made on her bed as much as she can. You'd be a little hurt by it if you didn't totally understand where she's coming from.

You grab her wrist before she can work herself up too much. “Relax, sis. When’s the last time mom came into either of our rooms unannounced? We’re safe as long as we’re not too loud.” You also kind of want to just work her up again and force her to hide her moans, but you figure she’s not the type to appreciate that. At least not yet.

She glares at you, but it’s obvious she’s just worried. “We still have to be careful! I… don’t want to mess this up, either.”

You nod and help her clean up the rest of the mess, putting your clothes back on and somehow managing not to look like you’ve just had your sister fuck you into a moaning mess. Before you leave her room to pretend everything’s back to normal while your parents are home, though, you can’t resist whispering one last thing in her ear.

“The bathroom has a good lock and muffles sound pretty well. Looking forward to making you feel bopping tonight, too.”

The thought of her flustered expression will have to be enough to tide you over until then.

**Author's Note:**

> My headcanon is that they bang to a YouTube mashup of Roselia and PasuPare songs. Thanks for coming to my TED talk.


End file.
